Topical fertility promoting product and manufacturing method

ABSTRACT

Vaginal lubricants that have salts which are biomatched to salts that are naturally present in the vagina facilitate intercourse without toxic effects. Topical substances that have a low buffering capacity to promote fertility by providing lubricity while minimizing disturbance to the natural pH levels present during intercourse. A low buffering capacity reduces the extent to which a product interferes with natural pH and buffering capacity of fluids that are present during intercourse.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation in part of U.S. patent applicationSer. No. 15/691,645, filed Aug. 30, 2017, which is a continuation inpart of U.S. patent application Ser. No. 15/294,340, filed Oct. 14,2016, now abandoned, which is a continuation of U.S. patent applicationSer. No. 14/636,035, filed Mar. 2, 2015, which issued as U.S. Pat. No.9,470,676, which application is based upon and claims the benefit under35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No.62/094,769, filed Dec. 19, 2014, which is incorporated herein byreference in its entirety for all purposes.

FIELD

This document relates to materials that are applied topically to thevagina to promote fertility.

INTRODUCTION

Portions of a human body typically secrete or produce various substancesthat may provide various benefits. For example, a mouth typicallysecretes saliva, which aids in digestion and provides lubrication forportions of the mouth. Microflora (e.g., including lactobacilli) of avagina typically produce lactic acid, which may protect the vagina fromvarious diseases, such as bacterial vaginosis (BV).

Often bodily secretions are supplemented with various over the counter(OTC) and/or prescription secretion supplements. For example, a personmay supplement secretions produced by their lips with an OTC lip balm.In another example, a female may supplement secretions produced by hervagina with an OTC or prescription personal lubricant.

However, pre-existing secretion supplements often include componentsthat were presumed to be safe but that actually harm the portion of thebody being supplemented. For example, pre-existing personal or vaginallubricants, such as K-Y® jelly, often include components that may damagethe vagina and/or may make the vagina more susceptible to disease. Forexample, pre-existing vaginal lubricants are often formulated to have pHvalues of 6-7, which are much higher than the acidic pH of the healthyvagina, which has a pH of around 3.5. This may allow sexuallytransmitted diseases (STDs) to occur and may lead to other diseases aswell, such as BV.

Similarly, Pre-seed®, a pre-existing pro-fertility lubricant, also doesnot have an acidic pH but rather has a somewhat alkaline pH of 7.29.This high pH alkalizes the vagina to promote the life of sperm, but bydoing so may make the vagina more susceptible to HIV and other STDpathogens.

Further, pre-existing personal lubricants are formulated with anosmolality much greater than an osmolality of a typical vagina. Usingsuch a personal lubricant may result in the cells of the vaginareleasing fluid to dilute the personal lubricant, which may result indeath of the cells, damage to the vagina, and/or subsequent dryness ofthe vagina.

Moreover, pre-existing vaginal products commonly include other variousingredients which are harmful to the vagina. For example, these vaginalproducts typically include detergents and surface-active agents,glycerol (glycerine) and other humectant/solvent excipients, and/orpreservatives which typically include chlorhexidine and/orethylenediaminetetraacetic acid (EDTA), among others. Detergents andsurface-active ingredients are harmful because they are markedly toxicto mucosal epithelia, including that of the vagina. Such detergents andsurface-active ingredients may include nonoxynol-9 and similardetergents, and glycerol monolaurate (GML). Glycerol (glycerine) andother humectant/solvent excipients are harmful because they increasevaginal susceptibility to disease. For example, Moench et al. (BMCInfectious Diseases 2010, 10: 331) reported that the followingexcipients markedly increased susceptibility to HSV-2 after a singleexposure: 5% glycerol monolaurate (GML) formulated in K-Y® WarmingJelly, 5% GML as a colloidal suspension in phosphate buffered saline,K-Y Warming Jelly alone, and both of its humectant/solvent ingredients(neat propylene glycol and neat polyethylene glycol (PEG-8)).

Conventional products that are marketed as being inserted into a vaginato promote fertility are typically formulated to match the pH of seminalfluids, which are alkaline, and buffered to preserve the alkalinity inthe presence of an acid. Alkaline substances in a vagina can be harmfulto a vagina, which is naturally acidic. Conventional fertility productsoften include toxic materials, or materials with a strong odor or flavorthat may harm users and diminish sexual experience.

SUMMARY

Embodiments of the present application include a vaginal lubricant thatcomprises a solvent, a viscosity modifier, up to 0.5% by weight of apotassium salt, up to 1.5% by weight of a sodium salt, and up to 0.5% byweight of a calcium salt, and has an osmolality of from 100-500 mOsm/Kg.The lubricant may further comprise up to 0.5% by weight of a magnesiumsalt. The potassium salt may be potassium chloride (KCl), the sodiumsalt may be sodium chloride (NaCl), the calcium salt may be calciumchloride (CaCl₂), and the magnesium salt may be magnesium chloride(MgCl₂).

In specific embodiments, the lubricant may have from 0.03% to 0.07% ofthe magnesium salt, from 0.15% to 0.35% of the potassium salt, from0.07% to 0.12% of the calcium salt, and from 0.30% to 1.0% of the sodiumsalt. The lubricant may be isotonic with human vaginal fluid. In anembodiment, the lubricant has an osmolality from 300-400 mOsm/Kg. Thelubricant may be non-toxic to the human vagina.

In one embodiment, the lubricant comprises from 0.15% to 0.35% of thepotassium salt, from 0.01% to 0.12% of the calcium salt, and from 0.30%to 1.0% of the sodium salt. Embodiments of the lubricant may be a gelwith a pH from 3.0-5.0. The lubricant may include up to 2% by weight oflactic acid.

A method of manufacturing a vaginal lubricant includes adding aviscosity modifier, a plurality of salts, and an acid to a solvent,wherein the plurality of salts comprises up to 0.5% by weight of apotassium salt, up to 1.5% by weight of a sodium salt, and up to 0.5% byweight of a calcium salt, so that the lubricant has a pH from 3.0 to5.0, and an osmolality of from 100-500 mOsm/Kg. The method may furtherinclude adding up to 0.5% by weight of a magnesium salt. The solvent maybe water. In an embodiment, the potassium salt is potassium chloride(KCl), the sodium salt is sodium chloride (NaCl), the calcium salt iscalcium chloride (CaCl₂), and the magnesium salt is magnesium chloride(MgCl₂). In addition, lactic acid may be added in an amount of from 0.2%to 2% by weight.

The potassium salt is added may be added in an amount of 0.15% to 0.35%,the sodium salt may be added in an amount from 0.15% to 0.35%, thecalcium salt may be added in an amount from 0.01% to 0.12%, and thesodium salt may be added in an amount from 0.30% to 1.0%. Theingredients may be added to achieve an osmolality from 300-450 mOsm/Kg.The substance may be iso-osmolal with human vaginal fluid.

A topical substance that promotes fertility when applied to a humanvagina may include a solvent, a plurality of salts dissolved in thesolvent, and a viscosity modifier, and have a pH of from 3 to 5, and abuffering capacity such that adding 5 millimoles of NaOH to 1 gram ofthe substance increases the pH by at least 1. The substance may have anosmolality of 500 mOsm/Kg or less. In an embodiment, the substance isiso-osmolal with healthy human vaginal fluid.

In an embodiment, the plurality of salts includes up to 0.5% by weightof a potassium salt, up to 1.5% by weight of a sodium salt, and up to0.5% by weight of a calcium salt. The salts may further include up to0.5% by weight of magnesium salt. In an embodiment, the substance hasfrom 0.03% to 0.07% of the magnesium salt, from 0.15% to 0.35% of thepotassium salt, from 0.01% to 0.12% of the calcium salt and from 0.30%to 1.0% of the sodium salt. The substance may further comprise up to0.02% by weight of sorbic acid, or from 0.001 to 0.01% by weight ofsorbic acid.

An embodiment of the fertility promoting substance has up to 0.05% byweight of lactic acid. The only acidic ingredients of the substance maybe the solvent and one or more of sorbic acid and lactic acid. Thesubstance may be free from alkaline ingredients, and it may be non-toxicto the human vagina.

The substance may have a buffering capacity such that adding 2millimoles of NaOH to 1 gram of the substance increases the pH by atleast 1, or a buffering capacity such that adding 1 millimole of NaOH to1 gram of the substance increases the pH by at least 1.

A method of forming a topical substance that promotes fertility whenapplied to a human vagina includes adding a plurality of salts and anacid to a solvent, and adding a viscosity modifier to the solvent toform a topical substance with a pH of from 3 to 5, and a bufferingcapacity such that adding 5 millimoles of NaOH to 1 gram of thesubstance increases the pH by at least 1. The plurality of salts mayinclude up to 0.5% by weight of a potassium salt, up to 1.5% by weightof a sodium salt, and up to 0.5% by weight of a calcium salt. Inaddition, up to 0.5% by weight of magnesium salt may be added.

In an embodiment, the plurality of salts includes from 0.03% to 0.07% ofa magnesium salt, from 0.15% to 0.35% of a potassium salt, from 0.01% to0.12% of a calcium salt, and from 0.30% to 1.0% of a sodium salt. Thesubstance may have an osmolality of 500 mOsm/Kg or less. In anembodiment, an amount of acids is added to the substance such thatadding 1 millimole of NaOH to 1 gram of the substance increases the pHby at least 1.

The present invention provides systems and methods for bio-matchingformulations (e.g., gels, creams, etc.) to a particular region (or part)of a living body, such as that of a human or other animal. Formulationsand methods of formulating thereof may provide compositions that bothsupplement secretions of the particular region of the living body andpromote the health of the particular region. In one embodiment, a methodof bio-matching a topical gel is provided. The method may compriseselecting a vagina of a living female body; identifying a secretion ofthe selected vagina; identifying a composition of the identifiedsecretion; and formulating the topical gel to match the identifiedcomposition of the identified secretion. The matching includes using apreselected type and quantity of lactic acid, and formulating to apreselected pH and salt composition.

In another embodiment, a topical gel for human use is provided. The gelmay comprise a formulation matched to a composition of a particular partof a human body. The formulation may include lactic acid, and theparticular part may be a vagina.

In another embodiment, a topical gel for human use may comprise aformulation including lactic acid having a racemic index in a range ofabout 50% L/50% D. The formulation may be matched to a composition (orchemistry thereof) of a particular part of a human body.

In another embodiment, a vaginal lubricant is provided. The lubricantmay comprise a formulation including lactic acid having a racemic indexthat is bio-matched but not bio-identical to a racemic index of naturallubricants in a generally healthy vagina.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram schematically depicting a composition of anidentified secretion of a selected region of a living body.

FIG. 2 is a block diagram schematically depicting a first formulationbio-matched to the composition of FIG. 1.

FIG. 3 is a block diagram schematically depicting a second formulationbio-matched but not bio-identical to the composition of FIG. 1.

FIG. 4 is a block diagram schematically depicting a third formulationbio-matched but not bio-identical to the composition of FIG. 1.

FIG. 5 is a block diagram of a female body, which schematically depictsa composition of an identified secretion of a vagina.

FIG. 6 is a block diagram schematically depicting a first formulationbio-matched to the composition of FIG. 5.

FIG. 7 is a block diagram schematically depicting a second formulationbio-matched but not bio-identical to the composition of FIG. 5.

FIG. 8 is a block diagram schematically depicting a third formulationbio-matched but not bio-identical to the composition of FIG. 5

FIG. 9 is a block diagram schematically depicting the bio-matchedformulation of FIG. 6 being applied to an unhealthy vagina of a femaleuser.

FIG. 10 is a block diagram of the female user of FIG. 9 afterapplication of the bio-matched formulation.

FIG. 11 is a flowchart depicting a method of bio-matching a topical gelto a living body.

DETAILED DESCRIPTION

FIG. 1 shows a living body 20, which may be that of a human or otheranimal. In some embodiments, body 20 may be a body of a plant. Body 20may have one or more regions (or components), such an eye region, an earregion, a vaginal region, a mouth region, and a rectal region amongothers. A selected region 22 of the one or more regions may produce oneor more secretions for one or more purposes (e.g., to produce one ormore desired effects). For example, a mouth region may produce saliva tolubricate the mouth region.

The one or more secretions of the selected region may include anidentified secretion 24. For example, identified secretion 24 may be asecretion that has been identified as contributing substantially toproducing the desired effect (e.g., mouth lubrication, digestion, tartarcontrol, etc.) and/or to promoting the health of the region.

As shown in FIG. 1, identified secretion 24 may include composition 26,which may include one or more chemical compositions, ionic compositions,molecular structures, and/or molecular compositions. For example, thecomposition may include a first portion of a first type of composition28, and a second portion of a second type of composition 30. FIG. 1shows the first and second portions including equal amounts ofcompositions 28 and 30. In some embodiments, composition 26 may includemore than two types of different compositions, and/or may includevarious ratios of portions thereof

In some embodiments, body 20 may be a generally healthy body, region 22may be a generally healthy region, and/or secretion 24 (and/or one ormore components of composition 26) may be identified as contributing tothe health of region 22 and/or body 20. For example, the composition ofregion 22 may correspond to a generally healthy composition (e.g.,associated with microbiota of a generally healthy, or eubiotic vagina).For example, one or more components of composition 26 or characteristicsor properties thereof may be associated with (or present in) generallyhealthy vagina secretions.

FIG. 2 shows a first formulation 32 that is bio-matched to body 20. Forexample, formulation 32 may be described as being bio-matched tocomposition 26. As shown, bio-matched formulation 32 includes a ratio ofcomposition 28 to composition 30 that is equal to the ratio ofcomposition 28 to composition 30 of secretion 24 in FIG. 1.

In some embodiments, formulations bio-matched to secretion 24 may haveratios that are not equal to the ratio of compositions of secretion 24.For example, FIG. 3 shows a formulation 34 having a higher ratio ofcomposition 28 to composition 30 than secretion 24, and FIG. 4 shows aformulation 36 including composition 28 but no composition 30.Formulations 34 and 36 may be described as being bio-matched but notbio-identical to a chemistry (or a composition) of secretion 24 (seeFIG. 1).

Formulation 34 and/or formulation 36 may be useful for promoting thehealth of region 22 (see FIG. 1) and/or the desired effect of secretion24. For example, composition 28 (or a characteristic of composition 28)may be identified as a significant contributor to the health of region22 and/or to the desired effect of secretion 24. For example, a higherratio of composition 28 to composition 30 may be identified as promotingthe health of region 22, in which case formulation 34 and/or formulation36 may be applied to region 22 (or to another body having acorresponding region deficient in composition 28) to increase a supplyof composition 28 in that region.

Bio-matching a formulation to body 20 may involve “bio-balancing” theformulation to body 20. For example, ingredients (or compositions) thatmay be foreign to, produced by, or present in body 20 may be identifiedas possibly (or actually) detracting from (or harming) the health ofregion 22 (or body 20 as a whole). In this case, formulations 32, 34,and/or 36 may be bio-balanced by avoiding inclusion of one or more ofthese possibly or actually harmful ingredients (or compositions).

In some embodiments of bio-balancing a formulation to a vagina, harmfulingredients to avoid may include detergents and surface-active agents,glycerol (or glycerine) and other humectant/solvent excipients, one ormore preservatives such as chlorhexidine and EDTA, salt in aconcentration that makes the formulation not isotonic in the vagina,and/or acid in a concentration that does not match that of a healthyvagina.

Typically, portions (or regions) of male and female human bodies secretevarious natural substances (or secretions). For example, a portion of afemale human body or a male human body (e.g., a gland, organ, or floraassociated with the portion or an organ) may secrete or produce one ormore particular substances (e.g., lactic acid, saliva, etc.) for one ormore particular functions (e.g., lubricating, moisturizing, cellprotection, cell repair, protection from pathogens or foreign mattersuch as dust, etc.).

For example, the female body may include eyes secreting a firstsubstance, a scalp secreting a second substance, ears secreting a thirdsubstance, nostrils secreting a fourth substance, a mouth secreting afifth substance (e.g., saliva), lips of the mouth secreting a sixthsubstance, armpits secreting a seventh substance, nipples secreting aneighth substance (e.g., pheromones), an epidermis secreting a ninthsubstance, genitalia secreting a tenth substance (e.g., lactic acidproduced by microflora living in the genitalia), a rectum secreting aneleventh substance, and feet secreting a twelfth substance.

The male body may include similar portions secreting (or producing)similar substances. However, due to differences between males andfemales (e.g., hormonal differences, genetic differences, among others)portions of the male body may differ from portions of the female body,and portions of the male body may secrete substances (e.g., pheromones)that are different than the substances secreted by the female body. Forexample, the male may include a penis and a scrotum secreting respectivethirteenth and fourteenth substances, and a mouth of the male maysecrete saliva having a composition that is different than a compositionof saliva from the mouth of the female.

The genitalia (commonly referred to as a vagina) of the female humanbody may include labia majora, labia minora, a vagina, a cervix, auterus, a urethra, a clitoris, a mons pubis, a symphysis pubis, andovaries. Typically, the labia majora and the labia minor lead to thevagina, the cervix, and the uterus; and the urethra leads from theurinary bladder out of the female body through the labia minora and thelabia majora.

A generally healthy vagina may include (or produce, or have presenttherein) various natural lubricants. For example, microflora (orbacteria) of the vagina (e.g., lactobacilli) may produce a firstanti-microbial lubricant (e.g., lactic acid). Typically, microflora(e.g., vaginal bacteria) of a generally healthy vagina is dominated byLactobacillus crispatus, which generally produce equal amounts ofL-lactic acid and D-lactic acid. Further, a membrane of a vaginal wallof the vagina may produce a second lubricant (e.g., moisture), mucusglands of the cervix may secrete a third lubricant (e.g., differentvariations of mucus before and during ovulation), and glands, such asglandula vestibularis major located near an opening to the vagina, maysecrete a fourth lubricant (e.g., a fluid such as mucus) when the femaleis sexually aroused.

In particular, mucus from the glands of the cervix and/or moisture fromthe vaginal wall membrane may provide lubrication within the vagina, andthe fluid from the glandula vestibularis major may moisten the labialopening of the vagina, which may make contact with this area morecomfortable for the female.

Typically, the female and/or a sexual partner of the female may apply anadditional lubricant to components of the genitalia the female, such asthe vagina and/or the labia majora and the labia minora, to increaselubrication of the vagina, which may enhance the sexual experienceand/or prevent breakage of a condom. For example, the male 70 may roll acondom onto his penis, such that an inside portion of the condom is incontact with the penis. The male may then apply a personal lubricant,such as over the counter K-Y® jelly, to an outside portion of thecondom. The female and the male may then engage in sexual intercourse,with the over the counter lubricant providing additional lubricationbetween the outside portion of the condom and the vagina. However, aspreviously described, pre-existing lubricants often include components(such as detergents like Nonoxynol-9) that are not bio-balanced to ahealthy vaginal environment, and application of such components may makethe vaginal environment more prone to disease or damage.

Accordingly, the applicant has discovered that formulating a composition(e.g., topical gel, cream, lubricant, etc.) to match a composition(e.g., chemical composition, and/or characteristics thereof) of asecretion of a selected region of a human body (e.g., a healthy vagina)may provide or enhance a desired effect (e.g., lubrication) and promotehealth.

For example, FIG. 5 shows a schematic representation of a female body40. A vagina 60 of body 40 may secrete one or more substances (orsecretions), as previously described. The one or more substances mayinclude an identified secretion 80 having a composition 100. If vagina60 (and/or body 40) is relatively or generally healthy, then composition100 may include L-lactic acid 102 (i.e., L-enantiomers) and D-lacticacid 104 (D-enantiomers), which are the two optical isomers of lacticacid. For example, microflora of a generally healthy vagina typicallyproduces lactic acid comprising approximately 50% L-lactic acid and 50%D-lactic acid (i.e., lactic acid having a racemic index of about 50%L/50% D). In contrast, it has been found that BV more commonly occurs invaginas with microflora that produce a large percentage of L-lactic acidand produce only a small percentage (or no percentage) of D-lactic acid.

To provide improved lubrication and vaginal health, applicant hasformulated a vaginal lubricant that substantially matches an actualcomposition and/or characteristic of healthy vaginal secretions and thatavoid inclusion of harmful ingredients (e.g., detergents, surface-activeagents, glycerol, chlorhexidine, and EDTA). The result is a formulationthat is bio-matched (or bio-balanced) to healthy vaginal secretions.Such a bio-matched vaginal lubricant should not include (or avoidinclusion of) any ingredient that might injure healthy vaginallactobacilli. Rather, the bio-matched vaginal lubricant may include oneor more of the following components and/or characteristics (orproperties) that are substantially matched to the components and/orcharacteristics (or properties) of healthy vaginal secretions:

-   -   an aqueous gel component—for example, the bio-matched vaginal        lubricant may include a gel that does not include glycerol or        other solvents, but only water (or comprises mainly water), as        is true for mucus secretions of a healthy vagina;    -   one or more viscoelastic properties—for example, the bio-matched        vaginal lubricant may use a safe and natural polymer to create a        gel with viscoelastic properties that match those of vaginal        secretions (e.g., mucus) of a healthy vagina, which may include        not only matching a viscosity of the vaginal secretions at a        given shear rate, but also across a broad range of shear        rates—more specifically, mucus of the vagina is a        “shear-thinning” lubricant (e.g., a gel that becomes very        slippery, and has a low viscosity when the gel is being sheared,        as in the act of intercourse), and matching the viscoelastic        properties of the vaginal lubricant to the mucus of the vagina        may provide for the gel of the bio-matched vaginal lubricant not        dripping out of the vagina, but remaining in the vagina and        becoming very slippery with a low viscosity only when being        sheared;    -   an isotonic property—for example, the bio-matched vaginal        lubricant may be formulated to have a salt composition that        makes the bio-matched vaginal lubricant isotonic in the vagina        (e.g., when the bio-matched vaginal lubricant is in the vagina,        the bio-matched vaginal lubricant will not cause water to be        secreted into the vagina, nor cause water to be absorbed out of        the vagina);    -   an isotonic property that matches as close as possible the salts        present in a vaginal secretion (the salts in a vaginal secretion        include sodium, potassium, calcium, and magnesium).    -   a pH property—for example, the pH of the bio-matched vaginal        lubricant may be formulated to closely match the pH of a        healthy, or eubiotic vagina (e.g., pH 3.8±0.3%);    -   a lactic acid component—for example, the bio-matched vaginal        lubricant may be acidified with ˜1±0.5% lactic acid, which is a        concentration that may match that of a healthy vagina; and    -   a racemic lactic acid component—for example, the bio-matched        vaginal lubricant may include lactic acid that is an essentially        racemic (equal) mix of the two optical isomers of lactic acid        (i.e., the D- and L-isomers) to match the mixture of these        isomers in a healthy vagina—more specifically, a healthy vagina        is typically acidified by lactobacilli that produce both D- and        L-isomers of lactic acid, but only a minority of women have        these healthy, protective lactobacilli, and most other women        either have few if any lactobacilli or have strains of        lactobacilli that fail to make the D-isomer, and thus the        bio-matched vaginal lubricant may be formulated to healthy        vaginal secretions by including an approximately even mix of the        two isomers (i.e., a racemic mix of D- and L-isomers of lactic        acid).

With respect to achieving the desired biomatching property recitedabove, applicant has learned it is particularly important to biomatchiso-osmolality, pH, and 1% by weight racemic acid. The isotonic propertyrecited above involves a salt composition that is isotonic with vaginalfluid. Isotonicity can be achieved with variations in sodium, andpotassium chlorides as well as with other osmotically active compounds.

Osmolality of healthy vaginal secretions has been measured, and usingthat measurement, the invention includes a gel that biomatchesosmolality to that of a healthy vagina. Based upon that biomatching, theinvented lubricant, including a gel version, is as close to beingisotonic as is possible. Biomatching, that is, matching the osmolalityof vaginal secretions is the best way to achieve isotonicity, given theabsence of any direct observations of fluid movement into or out of thevagina. The invented lubricant is isotonic, that is, for example, thegel version is effective to lubricate a human vagina that is neither:(i) hypertonic (causes the vaginal epithelium to secrete fluid thatdilutes the lubricant which can cause toxicity in the vagina), nor (ii)hypotonic (causes fluid to be withdrawn from the vagina and drying it).

Further, the applicant has found that formulating a vaginal lubricant tomatch the vaginal acidity of a healthy vagina, particularly by includinglactic acid in the formulation, and more specifically by includinglactic acid that is substantially racemic, kills HIV and many otherpathogens.

Recent studies have established harm caused to vaginal epithelial tissue[1]. Most of the widely used vaginal lubricants in the U.S. and Europeare strongly hyperosmolal, formulated with high concentrations ofglycerol, propylene glycol, polyquaternary compounds or otheringredients that make these lubricants 4 to 30 times the osmolality ofhealthy vaginal fluid. Hyperosmolal formulations have been shown tocause marked toxicity to human colorectal epithelia in vivo, andsignificantly increase vaginal transmission of genital herpes infectionsin the mouse/HSV model. They also cause toxicity to explants of vaginalepithelia, to cultured vaginal epithelial cells, and increasesusceptibility to HIV in target cells in cell cultures.

Hyperosmolal lubricants induce greater epithelial damage than hypo- andiso-osmolal lubricants. Given the level of breach in the epithelialbarrier by hyperosmolal lubricants, there is potential of an increase insusceptibility to sexually transmitted infections such as HIV and HSV inindividuals who are regular users of hyperosmolal lubricants. Sucheffects could be attributed to reduction in barrier integrity of theepithelium, which makes the epithelium “leaky” to allow viral andmicrobial entry, and alteration of the microbiota in the vaginalenvironment.

Hyperosmolal personal lubricants such as KY Jelly, and the surfactant N9have been found to be toxic to lactobacilli that can help protectagainst infections by acidifying the vagina with lactic acid, a broadantiviral and anti-bacterial agent. While toxicity of hypo-osmolalagents is minimal, hyperosmolal concentrations of glycerol and propyleneglycol cause obvious toxicity that increases markedly as the osmolalityincreases.

Lubricants containing glycerin/glycol, propylene glycol, andPolyethylene glycol (PEG-8) as one of the top four ingredients areassociated with marked reduction in barrier properties and tissuemorphological damage. The presence of glycerin as an ingredient may alsocontribute to an increase in osmolality which results in the loss of theapical layer in RepHresh exposed Epivaginal tissues. The reduction inbarrier function has been shown quantitatively by a reduction intrans-epithelial electrical resistance (TEER).

Historically, the significance of a highly toxic agent, the detergentnonoxynol-9 (N9), was not adequately realized until after performinglarge HIV prevention trials of N9. N9 was, and still is, used as avaginal contraceptive. Despite its significant toxic effects, it doesnot cause obvious pain or discomfort in most users.

Similarly, hyperosmolal lubricants cause little or no obvious pain ordiscomfort to most users. However, they have been shown to be toxicnonetheless, and to increase susceptibility to STDs. Sexual lubricantshave been associated in several studies with increased risk of episodesof bacterial vaginosis, and most sexual lubricants are hyperosmolal withrespect to the osmolality of healthy vaginal fluids. Hyperosmolalvaginal lubricants disrupt barrier functions of the basal and parabasallayers and shedding of the apical layers, which suggest osmolalityinduced disruption of epithelial barrier may be one of the mechanisms bywhich use of vaginal lubricants is associated with the risk of bacterialvaginosis and may increase susceptibility to sexually transmittedinfections.

FIG. 6 shows a first formulation 106 that is bio-matched to a chemistryof body 40 of FIG. 5 (e.g., to a chemistry of secretion 80 of vagina60). For example, FIG. 6 shows formulation 106 including 50% L/50% Dracemic lactic acid. In some embodiments, formulation 106 may includelactic acid having a racemic index of about 10% L/90% D. In someembodiments, formulation 106 may include lactic acid having a racemicindex of about 20% L/80% D. In some embodiments, formulation 106 mayinclude lactic acid having a racemic index of about 30% L/70% D. In someembodiments, formulation 106 may include lactic acid having a racemicindex of about 40% L/60% D. In some embodiments, formulation 106 mayinclude lactic acid having a racemic index of about 60% L/40% D. In someembodiments, formulation 106 may include lactic acid having a racemicindex of about 70% L/30% D. In some embodiments, formulation 106 mayinclude lactic acid having a racemic index of about 80% L/20% D. In someembodiments, formulation 106 may include lactic acid having a racemicindex of about 90% L/10% D. In some embodiments, formulation 106 mayinclude D-lactic acid, and no L-lactic acid.

In some embodiments, the racemic lactic acid (or lactic acid havinganother suitable racemic index) may comprise about 1% of formulation106. For example, the racemic lactic acid may comprise about 0.5% toabout 1.5% of formulation 106. In other embodiments, the racemic lacticacid (or lactic acid having another suitable racemic index) may compriseother suitable percentages of formulation 106. In some embodiments, theracemic lactic acid may be synthetically-derived. In other embodiments,the racemic lactic acid may be naturally-derived. Applying formulation106 to vagina 60 may lubricate vagina 60, and may promote the health ofvagina 60.

FIGS. 7 and 8 show respective formulations 108 and 110, which may beconsidered as bio-matched to composition 100 of secretion 80 of FIG. 5.For example, FIG. 7 shows formulation 108 including lactic acid having aracemic index of 30% L/70% D, which may be suitable for application to avagina that is slightly deficient in D-lactic acid. FIG. 8 showsformulation 110 including D-lactic acid, but no L-lactic acid, which maybe suitable for application to a vagina that has a greater deficiency ofD-lactic acid (or does not produce any D-lactic acid at all).

FIG. 9 shows a schematic representation of a female user 112 having avagina 114 that produces a secretion 116. Secretion 116 may include acomposition 118, which may comprise lactic acid including L-lactic acid120 and D-lactic acid 122. As shown, the lactic acid of secretion 116has a racemic index of 80% L/20% D, which may be associated with agenerally unhealthy condition of vagina 114 (or a condition prone todisease). Application of formulation 106 to vagina 114 may bothlubricate vagina 114 and promote the health of vagina 114 (and femaleuser 112). For example, formulation 106 may be added to secretion 116 toproduce a supplemented secretion 124 (see FIG. 13).

FIG. 13 shows a schematic representation of female user 112 afterapplication of formulation 106 (see FIG. 12) to vagina 114. As shown,supplemented secretion 124 of vagina 102 includes lactic acid having aracemic index of about 62.5% L/37.5% D, which may more closely match thelactic acid produced by microflora of a healthy vagina.

FIG. 14 shows an exemplary method, generally indicated at 200, ofbio-matching a topical gel (or cream, lubricant, or other suitablesubstance) to a living body.

Method 200 may include a step 202 of selecting a region of the body.Step 202 may involve selecting a region including one or morecomponents, such one or more glands, one or more organs, and/or flora(e.g., microflora including bacteria) that secrete various substances.For example, these components may secrete one or more particularsubstances (e.g., lactic acid, saliva, etc.) for one or more particularfunctions (e.g., lubricating, moisturizing, cell protection, cellrepair, excretion of waste, protection from pathogens or foreign mattersuch as dust, etc.). The selected body may be a human body, and theselected region may be a vagina.

Method 200 may include a step 204 of identifying a secretion of theselected region. Step 204 may involve selecting a secretion produced by(or present in) a generally healthy region, such as a generally healthyvagina.

Step 204 may involve identifying a secretion that a relatively healthybody (or part thereof) produces. For example, microflora of a generallyhealthy vagina typically produces lactic acid comprising approximately50% L-lactic acid (i.e., L-enantiomers) and 50% D-lactic acid (i.e.,D-enantiomers). In contrast, as previously described, BV more commonlyoccurs in vaginas with microflora that produce lactic acid with littleor no percentage of D-lactic acid. Accordingly, step 204 may involveidentifying lactic acid having L-enantiomers and D-enantiomers.

Method 200 may include a step 206 of identifying a composition (e.g.,chemical composition, molecular composition, ionic composition, orcharacteristics or properties thereof) of the identified secretion. Step206 may involve identifying lactic acid. Step 206 may involveidentifying lactic acid having a racemic index in a range of about 50%L/50% D.

Method 200 may include a step 208 of formulating the topical gel to(substantially) match the identified composition of the identifiedsecretion. Step 208 may involve selecting lactic acid that isapproximately racemic. Step 208 may involve selecting synthetic acid.Step 208 may involve selecting racemic synthetic acid. Step 208 mayinvolve selecting pure racemic synthetic acid having a racemic index of50% L/50% D. Step 208 may involve formulating the topical gel to includeabout 1% lactic acid (synthetic and/or racemic). In some embodiments,step 208 may involve bio-balancing the topical gel to avoid (or byavoiding) inclusion of one or more ingredients that are toxic (orharmful) to microbiota of the generally healthy vagina (or any vagina).Examples of ingredients that are toxic (or harmful) to the microbiota ofa vagina include detergents, surface-active agents, glycerol, many typesof preservatives including chloride and EDTA, saltconcentrations/formulations that make the formulation non-isotonic inthe vagina, and acid/base concentrations/formulations that do not matchthe pH of the generally healthy vagina.

Method 200 may further comprise applying the topical gel to the selectedregion of the human body (or a region of another human bodycorresponding to the selected region). For example, method 200 mayfurther comprise applying the topical gel to a vagina. For example,applying the topical gel may involve rolling a condom onto a penis, suchthat an inner surface of the condom contacts the penis; disposing thetopical gel onto an outer surface of the condom; and bringing the vaginainto contact with the outer surface of the condom.

In some embodiments, the topical gel may be disposed on the condom priorto the condom being rolled onto the penis. For example, the topical gelmay be disposed on the condom (e.g., the outer and/or inner surface)during a manufacturing and/or packaging step of the condom.

In other embodiments, the topical gel may be provided in a package ortube that is separate from a package containing a condom. For example,the topical gel may be provided in a stand-alone container. The user mayopen the container and apply the topical gel directly to the vagina,directly to the penis, and/or to any suitable surface of a condom.

In some embodiments, method 200 may further comprise applying thetopical gel to a suitable medical device. For example, the topical gelmay be suitable for lubricating one or more implements used during apelvic exam, such as an outer surface of a glove disposed on a hand of agynecologist.

EXAMPLE 1

The following is to prepare a vaginal lubricant according to a firstversion of the invention, with percentages by weight of the totalformulation shown parenthetically after each component. Certifiedorganic aloe vera powder (95%), commercially available under thetrademark SD 200×™ is hydrated in a separate mixing tank. Agar (0.2%) isadded to hydrated aloe vera powder, and the mixture is pasteurized byheating it to 160 degrees F. for about thirty (30) minutes. Afterallowing the mixture to cool to about 115 degrees F., Xanthan gum (3.1%)is added. The following inorganic ingredients are combined in a separatemixing container potassium sorbate (0.25%), sodium benzonate (0.20%) andnatural flavor (0.35%). After being suitably mixed, the inorganicingredients are added to the aloe vera mixture. Lactic acid (0.9%) issuitably mixed into the aloe vera mixture to match to the desired pH ofvaginal secretions. The resulting mixture is tested at completion andprior to dispensing into commercial containers for microbial count.Microbial count is tested by using commercially recognized bacterialchallenge tests, to meet the standard of no more than ten colony formingunits (CFUs) present. Other quality control tests are performed,including commercially known 30-day shelf/oven testing, and freeze/thawtesting.

EXAMPLE 2

The following is to prepare a vaginal lubricant according to a secondversion of the invention, with percentages by weight of the totalformulation shown parenthetically after each component. Certifiedorganic aloe vera powder (95%), commercially available under thetrademark SD 200×™ is hydrated in a separate mixing tank. Agar (0.2%) isadded to hydrated aloe vera powder, and the mixture is pasteurized byheating it to 160 degrees F. for about thirty (30) minutes. Afterallowing the mixture to cool to about 115 degrees F., Xanthan gum (3%)is added. The following inorganic ingredients are combined in a separatemixing container potassium sorbate (0.25%), sodium benzonate (0.20%) andnatural flavor (0.35%). After being suitably mixed, the inorganicingredients are added to the aloe vera mixture. Racemic lactic acid (1%)is suitably mixed into the aloe vera mixture to bring the pH of thatmixture within the range of 3.5-3.9. Microbial count is tested by usingcommercially recognized bacterial challenge tests, to meet the standardof no more than ten colony forming units (CFUs) present. Other qualitycontrol tests are performed, including commercially known 30-dayshelf/oven testing, and freeze/thaw testing.

EXAMPLE 3

The following is to prepare a vaginal lubricant according to a thirdversion of the invention, following a procedure as described inconnection with Examples 1 and 2, and with percentages by weight of thetotal formulation shown parenthetically after each component.

Percentage Component by weight Function Water 94.5-97.5%  SolventHydroxyethylcellulose  0.5-1.5% Viscosity modifier Carrageenan 0.25-.90%Binder Ceratonia Siliqua (Carob) Gum 0.07-.30% Binder Xanthan Gum0.07-.30% Binder Sodium Chloride 0.25-.70% Osmolality modifier LacticAcid  0.5-1.5% pH adjuster Sodium Hydroxide 0.07-.30% pH adjusterPotassium Sorbate  0.15-.4% Preservative Sodium Benzoate  0.15-.4%Preservative Calcium Chloride 0.005-.02%  Viscosity modifier

According to recently published test results, healthy vaginal secretionshave an osmolality of 370+/−10 mOsm/Kg, which is higher than theosmolality of most other bodily fluids, which is about 290+/−10 mOsm/Kg.The osmolality of this above-identified version of the invention is350+/−10 mOsm/Kg.

The primary gelling agent in the third version is HEC(hydroxyethylcellulose), and the secondary gelling agent is Carrageenan,a nontoxic material made from seaweed. Utilizing Carrageenan causes thethird version to have the added feature of tending to minimize HSV andHPV infections. The primary salt ions used in the third version are Na,K, Cl, and Ca, and that same combination is found in the vagina. Whilethe concentrations of those four salts are not identical to those in ahealthy vagina, the combination of those four salts have been adjustedsuch that this third version has an osmolality that matches theosmolality of healthy vaginal secretions.

Biomatching salt content to healthy vaginal fluid has numerous benefits.In addition to providing a healthy osmolality, biomatching salt contentminimizes disruption of natural conditions to which bacterial flora areadapted. Introducing a substance that alters natural conditions can beharmful to lactobacillus and other vaginal flora. Accordingly,biomatched salt content promotes general health. Vaginal fluids arefluids that are present in a normal healthy vagina, and may comprisesecretions from the endocervix and the vaginal epithelium.

Measured data suggests that healthy vaginal fluids have significantquantities of potassium salt, sodium salt, calcium salt, and magnesiumsalt. Embodiments of a biomatched lubricant may include potassium saltas potassium chloride (KCl), sodium salt as sodium chloride (NaCl),calcium salt as calcium chloride (CaCl₂), and magnesium salt asmagnesium chloride (MgCl₂). Embodiments may include up to 0.5% by weightof a potassium salt, up to 1.5% by weight of a sodium salt, up to 0.5%by weight of a calcium salt, and up to 0.5% by weight of magnesium salt.In some embodiments, the salts may be included in a range of from 0.03%to 0.07% of the magnesium salt, from 0.15% to 0.35% of the potassiumsalt, from 0.005% to 0.12% of the calcium salt, and from 0.30% to 1.0%of the sodium salt.

Low Buffering Capacity for Promoting Fertility

Embodiments of the present disclosure are directed to a product thatsafely lubricates the vagina while promoting fertility. Manyconventional vaginal lubricants have a pH that is roughly matched to thepH of the human vagina, which is acidic. However, semen is alkaline witha pH that is typically in the range of about pH 7.1-8.0. An acidicvaginal lubricant can lower the pH of semen, which can be toxic tosperm. Accordingly, conventional vaginal lubricants inhibit fertility byharming sperm.

Therefore, conventional fertility products typically have a pH that isformulated to promote sperm health. pH values of conventional fertilityproducts are typically in the range from about 7 to 8. In addition,conventional fertility products are typically buffered to maintain astable pH in the 7-8 range. The buffering capacity of conventionalfertility products causes them to neutralize the acidic environment ofthe vagina, which can cause harm to a user, including destruction ofnatural flora and damage to vaginal cells.

Fertility promoting products are often used by couples that are havingdifficulty conceiving. There are many physiological inhibitions tofertility that prevent or inhibit fertility regardless of the pH levelsduring intercourse. As a result, couples may use fertility productsfrequently for an extended period of time, which can cause significantdamage when the products are buffered to protect sperm. The additionaldamage to the vagina may make it even more difficult to conceive.Accordingly, conventional fertility products may end up harming usersand ultimately making it more difficult to conceive than it would be ifthose products were never used.

Embodiments of the present disclosure overcome the shortcomings ofconventional fertility products. In an embodiment, a product that isapplied to the vagina has a low buffering capacity. A product with lowbuffering capacity has minimal effect on the pH levels of fluids inwhich it is in contact, thereby minimizing the impact that the producthas on the natural pH levels that are present during intercourse.

In one embodiment, a product with minimal buffering capacity isformulated to have a pH within the range of a normal human vagina.Although there is no definitive consensus on a value or range of theacidity of a healthy vagina, it is generally recognized to be within therange of 3.1 to 4.5, and a majority of healthy vaginas have a pH of3.5-4.1. Accordingly, a product that promotes fertility in the vaginamay have an initial pH from 3.0-6.0, 3.1-4.5, or 3.5-4.1.

A useful designation concerning the buffering capacity of a buffersolution is the designation of the buffer's Van Slyke buffer value β.The Van Slyke buffer value β indicates the resistance of the buffer tochange in pH upon addition of a strong acid or base, and is defined bythe ratio ΔB/ΔpH, where B is the increment of completely dissociatedbase or acid in gram-equivalents per liter required to produce a unitchange in pH (Van Slyke, Biol. Chem. 52, 525-570, 1922). Thus, Slykesare the units of buffer strength (β) derived from the formula β=B/1pH,where B is millimoles (mM) of 1N strong acid or base.

The buffering capacity of semen has been measured at 35.6±12.3 slykes,where β₇₋₆=35.6±12.3 mM, and the buffering capacity of vaginal fluid hasbeen measured at 37.5±5 slykes, which may be expressed asβ_(4.2-5.2)=37.5±5 mM. [2]

A vaginal product that promotes fertility may have a buffering capacitythat is less than the buffering capacities of semen and vaginal fluids.In some embodiments, the buffering capacity of a vaginal product thatpromotes fertility is 50% or less, 25% or less, or 10% or less than avalue within the range of the buffering capacity of semen or vaginalfluid. More specifically, an embodiment of the present disclosure mayhave a buffering capacity of 20 slykes or less, 10 slykes or less, 5slykes or less, 2 slykes or less, or less than 1.0 slykes.

There are advantages and disadvantages to formulations within theseranges. When buffering capacity is higher, a fertility enhancementproduct can help preserve a natural pH from being altered by othersubstances that may be present during intercourse, such as otherfertility promoting products or materials that are otherwise meant toenhance pleasure during intercourse. On the other hand, when bufferingcapacity is lower, a formulation will minimize disruption to the naturalpH of vaginal secretions and sperm. A low buffering capacity can beachieved by minimizing the concentration of ingredients in a productthat buffer pH levels.

The following table provides an example of a set of ingredients that arepresent in an embodiment of a vaginal lubricant that promotes fertility.Embodiments of the present disclosure are not limited to the specificvalues and ingredients in the table.

EXAMPLE 4

Percentage Component by weight Function Water    90-99% SolventHydroxyethylcellulose  0.5-5.0% Viscosity modifier Sodium Chloride 0.1-1.5% Biomatched Salt Potassium Chloride 0.001-1.5% Biomatched SaltCalcium Chloride 0.001-1.5% Biomatched Salt Magnesium Chloride0.001-1.5% Biomatched Salt Lactic Acid   0-0.03% Weak acidic bufferPotassium Sorbate 0.001-0.1% Preservative & weak buffer Sorbic Acid0.001-0.1% Preservative

The primary constituent of the product described by Example 4 is waterwhich acts as a solvent. The water may be deionized or water or waterthat has otherwise been purified to remove materials that could reactwith other ingredients or biological fluids. Hydroxyethylcellulose ispresent as a viscosity modifier that creates a gel and provideslubricity. The listed functions of the ingredients are merelyillustrative, and other purposes are possible.

Persons of skill in the art will recognize that it is possible toprovide additional ingredients, and to substitute known ingredients forthe specific ingredients listed in Example 4 in other embodiments. Someof the key properties of Example 4 include an osmolality that isbiomatched to the osmolality of a vagina, salt content and pH that arebiomatched to vaginal secretions, and a buffer capacity that issignificantly lower than the buffer capacity of seminal fluids. Theformula of Example 4 does not include any materials that are toxic orotherwise harmful to the vagina in the listed concentrations—on thecontrary, most of the ingredients are naturally present in the humanvagina.

The hydroxyethlycellulose is included as a viscosity modifier, orgelling agent. A gel provides lubricity as well as cohesion betweenmolecules in a lubricant, which helps the lubricant to remain in thevagina during intercourse. When large amounts of viscosity modifier arepresent, formulations become tacky and lose lubricity. Persons of skillin the art will recognize that it is possible to use one or moreviscosity modifiers other than hydroxyethylcellulose to create anon-toxic biocompatible gel. Accordingly, embodiments are not limited tothe specific viscosity modifiers provided in the Examples.

Some embodiments have concentrations of ingredients that vary from theconcentrations provided in the table above. Sodium chloride may beprovided in concentrations from 0.5-1.0% or 0.65-0.85%, potassiumchloride may be provided in concentrations from 0.1-0.5% or 0.2-0.3%,calcium chloride may be provided in concentrations from 0.01-0.20% or0.06-0.12%, magnesium chloride may be provided in concentrations from0.01-0.15% or 0.03-0.07%, sorbic acid may be provided in concentrationsfrom 0.001-0.01% or 0.002-0.008%, and lactic acid may be provided inconcentrations from 0.00-0.05% or 0.00-0.15%. For a product thatpromotes fertility lactic acid may be present in a lower concentrationthan a product for general lubrication and vaginal health to minimizethe buffering capacity of the pro-fertility product.

In a lubricant that promotes fertility, salt content may be selected tobiomatch one or both of seminal plasma and vaginal fluids. Inparticular, magnesium is present in seminal plasma at levels that arenot found in vaginal fluids, so a magnesium salt that is not added to alubricant that is biomatched to vaginal fluids may be included in apro-fertility product. In a preferred embodiment, a lubricant thatpromotes fertility is formed by adding salts to approximately match acombination of seminal and vaginal fluids.

EXAMPLE 5

Batches of vaginal lubricant were prepared by combining the salts,sorbic acid, lactic acid and potassium sorbate with water and stirringvigorously. Hydroxyethylcellulose was sifted in while continuing to stirthe solution to create a gel. It was determined that lubricant preparedwith the ingredients and ranges described in Example 4 can be combinedto create lubricants with a pH within the range of 3.1-4.5, anosmolality of up to 500 mOsm/kg, and a buffer capacity of from about1-10 slykes. The osmolality values can be adjusted by varying the amountof salts, and the pH and buffering capacity can be adjusted by varyingthe amount of acid. Lubricants with such low buffering capacities willnot significantly alter the pH of the vagina, nor reduce thealkalinizing, sperm-supporting, action of semen. Its ionic compositionwill also support the viability of sperm.

The following paragraphs may provide further information regardingembodiments of the present disclosure.

A. A method of bio-matching a topical gel, the method comprising:selecting a region of a living body, wherein selecting the regioninvolves selecting a vagina; identifying a secretion of the selectedvagina; identifying a composition of the identified secretion; andformulating the topical gel to match the identified composition of theidentified secretion.

A1. The method of paragraph A, wherein the body is a human body.

A2. The method of paragraph A, wherein identifying the secretioninvolves identifying a secretion present in a generally healthy vagina.

A3. The method of paragraph A2, wherein identifying the composition ofthe identified healthy secretion involves identifying lactic acid.

A4. The method of paragraph A3, wherein identifying lactic acid involvesidentifying racemic lactic acid having a racemic index in a range ofabout 50% L/50% D.

A6. The method of paragraph A5, wherein selecting lactic acid involveschoosing an approximately racemic mixture with between 30% to 70% L andbetween 70% to 30% D.

A7. The method of paragraph A6, wherein formulating the topical gelinvolves formulating the topical gel to include about 1% of the selectedlactic acid.

A8. The method of paragraph A2, wherein formulating the topical gelinvolves bio-balancing the topical gel by avoiding inclusion of one ormore ingredients that are toxic to microbiota of the generally healthyvagina.

B. A topical gel for human use, the gel comprising: a formulationmatched to a chemistry of a particular part of a human body, theformulation including lactic acid.

B1. The gel of paragraph B, wherein the particular part of the humanbody is a vagina.

B2. The gel of paragraph 81, wherein the chemistry is a generallyhealthy chemistry associated with the vagina.

B3. The gel of paragraph B2, wherein the generally healthy chemistryincludes lactic acid having a racemic index of about 50% L/50% D.

B4. The gel of paragraph B3, wherein the formulation comprisesapproximately 1% lactic acid having a racemic index in a range of about30% L/70% D to 70% L/30% D.

B5. The gel of paragraph B4, wherein the racemic index of the 1% lacticacid is approximately 50% L/50% D.

C. A topical gel for human use, the gel comprising: a formulationmatched to a chemistry of a particular part of a human body, theformulation including lactic acid having a racemic index in a range ofabout 50% L/50% D.

C1. The gel of paragraph C, wherein the particular part is a vagina.

C2. The gel of paragraph C1, wherein the chemistry corresponds to agenerally healthy chemistry associated with flora of the vagina.

C3. The gel of paragraph C2, wherein the generally healthy chemistryincludes racemic lactic acid having a racemic index of about 50% L/50%D.

C4. The gel of paragraph C3, the lactic acid of the formulationcomprises about 1% of the formulation.

D. A vaginal lubricant, comprising: a formulation including lactic acidhaving a racemic index that is bio-matched but not bio-identical to aracemic index of natural lubricants in a healthy vagina.

D1. The lubricant of paragraph D, wherein the lactic acid of theformulation is naturally-derived.

D2. The lubricant of paragraph D, wherein the lactic acid of theformulation is synthetically-derived.

D3. The lubricant of paragraph D, wherein the racemic index of thelactic acid of the formulation is in a range of about 30% L/70% D to 70%L/30% D, and the racemic index of the natural lubricants is about 50%L/50% D.

D4. The lubricant of paragraph D3, wherein the lactic acid of theformulation is synthetic lactic acid comprising about 1% of theformulation, the synthetic lactic acid having a racemic index of about50% L/50% D.

D5. The lubricant of paragraph D, wherein vagina bacteria of the healthyvagina is dominated by Lactobacillus crispatus which produce lactic acidthat is included in the natural lubricants, the lactic acid of thenatural lubricants having a racemic index of approximately 50% L/50% D.

D6. The lubricant of paragraph D5, wherein the lactic acid of theformulation has a racemic index in a range of 80% L/20% D to 20% L/80%D, thereby resulting in the formulation being bio-matched to the naturallubricants of the healthy vagina.

The disclosure set forth herein encompasses multiple distinctembodiments with independent utility. These embodiments are not to beconsidered in a limiting sense as numerous variations are possible. Eachexample defines an embodiment disclosed in the foregoing disclosure, butany one example does not necessarily encompass all features orcombinations that may be eventually claimed. Where the descriptionrecites “a” or “a first” element or the equivalent thereof, suchdescription includes one or more such elements, neither requiring norexcluding two or more such elements. Further, ordinal indicators, suchas first, second or third, for identified elements are used todistinguish between the elements, and do not indicate a required orlimited number of such elements, and do not indicate a particularposition or order of such elements unless otherwise specifically stated.

[1] Seyoum Ayehunie, Ying-Ying Wang, Timothy Landry, StephanieBogojevic, Richard A. Cone, Hyperosmolal vaginal lubricants markedlyreduce epithelial barrier properties in a three-dimensional vaginalepithelium model, Toxicology Reports 5 (2018) 134-140.

[2] Rachna Rastogi, Jonathan Su, Alamelu Mahalingam, Justin Clark,Samuel Sung, Thomas Hope, Patrick F. Kiser, Engineering andcharacterization of simplified vaginal and seminal fluid simulants,Contraception 93 (2016) 337-346.

What is claimed is:
 1. A topical substance that promotes fertility whenapplied to a human vagina, the topical substance comprising: a solvent;a plurality of salts dissolved in the solvent; and a viscosity modifier;wherein the topical substance has a pH of from 3 to 5, and a bufferingcapacity such that adding 5 millimoles of NaOH to 1 gram of thesubstance increases the pH by at least
 1. 2. The topical substance ofclaim 1, wherein the substance has an osmolality of 500 mOsm/Kg or less.3. The topical substance of claim 1, wherein the substance isiso-osmolal with healthy human vaginal fluid.
 4. The topical substanceof claim 1, wherein the plurality of salts comprises: up to 0.5% byweight of a potassium salt; up to 1.5% by weight of a sodium salt; andup to 0.5% by weight of a calcium salt.
 5. The topical substance ofclaim 1, wherein the plurality of salts further comprises up to 0.5% byweight of magnesium salt.
 6. The topical substance of claim 5, whereinthe substance comprises: from 0.03% to 0.07% of the magnesium salt; from0.15% to 0.35% of the potassium salt; from 0.01% to 0.12% of the calciumsalt; and from 0.30% to 1.0% of the sodium salt.
 7. The topicalsubstance of claim 1, wherein the substance comprises: up to 0.02% byweight of sorbic acid.
 8. The topical substance of claim 7, wherein thesubstance comprises: from 0.001 to 0.01% by weight of sorbic acid. 9.The topical substance of claim 1, wherein the substance comprises: up to0.05% by weight of lactic acid.
 10. The topical substance of claim 1,wherein the only acidic ingredients are the solvent and one or more ofsorbic acid and lactic acid.
 11. The topical substance of claim 1,wherein the substance is free from alkaline ingredients.
 12. The topicalsubstance of claim 1, wherein the substance is a gel that is non-toxicto the human vagina.
 13. The topical substance of claim 1, wherein thebuffering capacity is such that adding 2 millimoles of NaOH to 1 gram ofthe substance increases the pH by at least
 1. 14. The topical substanceof claim 1, wherein the buffering capacity is such that adding 1millimole of NaOH to 1 gram of the substance increases the pH by atleast
 1. 15. A method of forming a topical substance that promotesfertility when applied to a human vagina, the method comprising: addinga plurality of salts and an acid to a solvent; and adding a viscositymodifier to the solvent, wherein the topical substance has a pH of from3 to 5, and a buffering capacity such that adding 5 millimoles of NaOHto 1 gram of the substance increases the pH by at least
 1. 16. Themethod of claim 15, wherein the plurality of salts comprises: up to 0.5%by weight of a potassium salt; up to 1.5% by weight of a sodium salt;and up to 0.5% by weight of a calcium salt.
 17. The method of claim 16,wherein the plurality of salts further comprises: up to 0.5% by weightof magnesium salt.
 18. The method of claim 15, wherein the plurality ofsalts comprises: from 0.03% to 0.07% of a magnesium salt; from 0.15% to0.35% of a potassium salt; from 0.01% to 0.12% of a calcium salt; andfrom 0.30% to 1.0% of a sodium salt.
 19. The method of claim 15, whereinthe topical substance has an osmolality of 500 mOsm/Kg or less.
 20. Themethod of claim 15, wherein the buffering capacity is such that adding 1millimole of NaOH to 1 gram of the substance increases the pH by atleast 1.